4. Curvature Studies of Unconstrained Thermal Barrier Composites

  1. Dongming Zhu and
  2. Kevin Plucknett
  1. O. Zubacheva1,
  2. J. Malzbender1,
  3. R. W. Steinbrech1,
  4. L. Singheiser1 and
  5. U. Schulz2

Published Online: 26 MAR 2008

DOI: 10.1002/9780470291238.ch4

Advances in Ceramic Coatings and Ceramic-Metal Systems: Ceramic Engineering and Science Proceedings, Volume 26, Number 3

Advances in Ceramic Coatings and Ceramic-Metal Systems: Ceramic Engineering and Science Proceedings, Volume 26, Number 3

How to Cite

Zubacheva, O., Malzbender, J., Steinbrech, R. W., Singheiser, L. and Schulz, U. (2005) Curvature Studies of Unconstrained Thermal Barrier Composites, in Advances in Ceramic Coatings and Ceramic-Metal Systems: Ceramic Engineering and Science Proceedings, Volume 26, Number 3 (eds D. Zhu and K. Plucknett), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470291238.ch4

Author Information

  1. 1

    Forschungszcntrum Jülich GmbH Institute for Materials and Processes in Energy Systems 52428 Jülich, Germany

  2. 2

    German Aerospace Center (DLR) Institute of Materials Research 51170 Cologne, Germany

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 2005

ISBN Information

Print ISBN: 9781574982336

Online ISBN: 9780470291238

SEARCH

Keywords:

  • electron;
  • alumina;
  • microstructure;
  • geometry;
  • thermoelastic

Summary

The curvature behavior of unconstrained thermal barrier composites was studied up to 1000°C using two layer (substrate + bond coat) and three layer (substrate + bond coat + top coat) specimens. Electron beam physical vapor deposited (EB-PVD) top coats on either EB-PVD or vacuum plasma sprayed (VPS) bond coats were tested on the same substrate material. Inelastic curvature behavior was recognized for both bond coat variants at temperatures above 800°C. Contrary to the relaxation related decrease of specimen curvature in case of EB-PVD bond coat, the VPS variant showed a pronounced increase during a 2 h dwell time at 1000°C. The effect could be related with isothermal expansion of the bond coat The results are discussed in terms of microstructural phase changes and the thermal history that the BCs experienced during the processing steps of thermal barrier composites.